Battery management device

Abstract

A battery management device for managing a battery mounted in a vehicle is provided with: an acquisition unit for acquiring, from the vehicle, data including information relating to the current of the battery and information relating to the start-up of the vehicle; a derivation unit that derives, on the basis of the data, an integrated value of the current to be charged and discharged by the battery and an average value of the current to be charged and discharged by the battery during the latest start-up period of the vehicle; and a determination unit that determines that external charging or replacement of the battery has been performed when the integrated value of the current is less than a first threshold value and the average value of the current is less than a second threshold value.

Description

Technical Field

[0001] The present disclosure relates to a battery management device that manages a battery mounted on a vehicle. Background Art

[0002] International Publication No. 2015 / 151848 discloses a detection device and a detection method that can accurately detect that a battery mounted on a vehicle has been replaced. Summary of the invention

[0003] In the detection method described in International Publication No. 2015 / 151848, a complex equivalent circuit model is used to detect that the battery has been replaced. Therefore, there is a problem that the load of the detection process becomes larger and the corresponding working hours increase. Therefore, there is room for research on the method of detecting battery replacement.

[0004] The present disclosure provides a battery management device that can detect, with high accuracy, whether a battery has been replaced, etc., using a simple method.

[0005] In order to solve the above-mentioned problem, a technical solution disclosed in the present invention is a battery management device for managing a battery mounted on a vehicle, the battery management device comprising: an acquisition unit, which acquires data including information related to the battery current and information related to the starting (starting) of the vehicle from the vehicle; an export unit, which exports the cumulative value of the battery charging and discharging current so far and the average value of the battery charging and discharging current during the most recent vehicle starting period based on the data; and a determination unit, which determines that external charging or replacement of the battery has been performed when the cumulative value of the current is less than a first threshold value and the average value of the current is less than a second threshold value.

[0006] According to the battery management device disclosed in the present invention, without using a complex equivalent circuit model that increases the load of detection processing, it is possible to accurately detect whether the battery is externally charged or replaced based on the integrated value and average value of the battery charging and discharging current that can be easily obtained. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] Hereinafter, features, advantages, and technical and industrial significance of exemplary embodiments of the present invention will be described with reference to the accompanying drawings, in which like reference numerals denote like elements, and wherein:

[0008] Figure 1 is a schematic diagram of a battery management device according to an embodiment of the present disclosure;

[0009] Figure 2 It is a processing flow chart of the battery replacement and other determination control (first embodiment) executed by the battery management device;

[0010] Figure 3 is a schematic diagram of the starting voltage and current integrated value of the battery in the first embodiment;

[0011] Figure 4 It is a schematic diagram of the average voltage and current of the battery;

[0012] Figure 5A It is a processing flow chart of the battery replacement and other determination control (second embodiment) executed by the battery management device;

[0013] Figure 5B It is a processing flow chart of the battery replacement and other determination control (second embodiment) executed by the battery management device;

[0014] Figure 6 is a schematic diagram of the starting voltage and current integrated value of the battery in the second embodiment;

[0015] Figure 7 It is a processing flow chart of the battery replacement and other determination control (third embodiment) executed by the battery management device;

[0016] Figure 8 This is an example of a data map for deriving the moving average coefficient α1 used in the third embodiment;

[0017] Fig. 9 This is a data mapping example for deriving the moving average coefficient α2 used in the third embodiment;

[0018] Fig. 10A It is a processing flow chart of an application example of battery replacement and other determination control executed by a battery management device;

[0019] Fig. 10B It is a processing flow chart of an application example of battery replacement and other determination control executed by a battery management device;

[0020] Fig. 10C This is a processing flow chart of an application example of battery replacement and other determination control executed by a battery management device. DETAILED DESCRIPTION

[0021] The battery management device disclosed in the present invention uses battery conditions such as the integrated value of the battery's charge and discharge current, the average value of the charge and discharge current, and the starting voltage that can be easily obtained from the battery, and detects whether the battery is being externally charged or replaced based on changes in the battery conditions, deviation (difference, discrepancy) tendencies, etc.

[0022] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings.

[0023] Implementation

[0024] constitute

[0025] Figure 1 1 is a block diagram showing a schematic configuration of a battery management system 1 including a battery management device 20 according to an embodiment of the present disclosure. Figure 1 The illustrated battery management system 1 is configured to include a vehicle 10 and a battery management device 20 .

[0026] (1) Vehicle

[0027] The vehicle 10 is connected to the battery management device 20 so as to be communicable. The vehicle 10 is, for example, a car, and includes at least a battery 11, a battery information acquisition unit 12 built into the battery 11, and a data transmission unit 13. Figure 1 In FIG. 1 , an example is shown in which a single vehicle 10 is connected to the battery management device 20 in a communicable manner. However, a plurality of vehicles 10 may be connected to the battery management device 20 in a communicable manner.

[0028] The battery 11 is a secondary battery that can be charged and discharged, such as a lithium ion battery or a lead storage battery. An auxiliary (accessory) battery can be exemplified as the battery 11. The battery 11 can be charged, for example, from an external charger via a direct connection through a jumper cable or the like. In addition, when the battery 11 deteriorates (ages), it is replaced with a new one.

[0029] The battery information acquisition unit 12 acquires battery information related to the state of the battery 11. The battery information includes the voltage, current (charging current, discharging current), and temperature of the battery 11. Such battery information can be detected using a detection element (voltage sensor, current sensor, temperature sensor, etc.) not shown in the figure provided on the battery 11. In addition, the battery information acquisition unit 12 may be configured outside the battery 11, and need not be built in the battery 11.

[0030] In the present embodiment, the charging current flowing into the battery 11 for charging is set to a positive value, the discharging current flowing out of the battery 11 for discharging is set to a negative value, and the current integrated value obtained by summing up the charging current and the discharging current is set to the charge and discharge amount of the battery 11. The charge and discharge amount is defined as "0 (zero)" when the battery 11 maintains a fully charged state (SOC = 100%), and is expressed as a negative value smaller than zero according to the remaining capacity of the battery 11.

[0031] The data transmission unit 13 is configured to have a function of controlling communication between the vehicle 10 and the battery management device 20. The data transmission unit 13 transmits data including the battery information acquired by the battery information acquisition unit 12 and information related to the start of the vehicle 10 to the battery management device 20. Examples of the information related to the start of the vehicle 10 include information such as the timing of the start of the vehicle 10 (IG-ON time) and the start period of the vehicle 10 (time from the start to the end of the start). The data transmission unit 13 is realized by, for example, a data communication module (DCM).

[0032] (2) Battery management device

[0033] The battery management device 20 is communicatively connected to the vehicle 10. The battery management device 20 is, for example, a cloud server, and includes at least a data receiving unit 21, an external charging / exchange detection unit 22, and a data output unit 23.

[0034] The data receiving unit 21 is configured to have a function of controlling communication between the battery management device 20 and the vehicle 10 . The data receiving unit 21 can receive data transmitted from the vehicle 10 .

[0035] The external charging / exchange detection unit 22 is a structure for detecting that the battery 11 is externally charged or that the battery 11 is replaced based on the data (battery information, startup information) received by the data receiving unit 21. Details of the detection method performed by the external charging / exchange detection unit 22 will be described later.

[0036] When the external charging / exchange detection unit 22 detects that the battery 11 is externally charged or replaced, the data output unit 23 can output the detection. Examples of the output destination include the user of the vehicle 10, a dealer, and the like.

[0037] control

[0038] Next, refer to Figures 2 to 9 The control performed by the battery management device 20 according to the present embodiment will be described. The control described below is performed by the battery management device 20 for each vehicle 10 .

[0039] (1) First Embodiment

[0040] Figure 2 1 is a flowchart for explaining the processing procedure of the first embodiment of the battery replacement determination control executed by the battery management device 20. The first embodiment is a method using the state of the battery 11 when the vehicle is running. Figure 2 The battery replacement and other determination control illustrated is repeatedly started, for example, every time the ignition of the vehicle 10 is turned on (IG-ON) and the vehicle 10 is started.

[0041] S201

[0042] The data receiving unit 21 receives data transmitted from the data transmitting unit 13 of the vehicle 10. The data received by the data receiving unit 21 includes at least information about the current of the battery 11 and information about the start of the vehicle 10. The received data may be stored in a predetermined storage unit (not shown) or the like. After the data receiving unit 21 receives the data, the process proceeds to S202.

[0043] S202

[0044] The external charging / exchange detection unit 22 updates (derives) the current integrated value of the battery 11. Specifically, the external charging / exchange detection unit 22 calculates the charge and discharge amount (this value) of the battery 11 from the last start to the current start based on the current (this value) of the battery 11 included in the data received in S201. The calculated charge and discharge amount (this value) is added to the current integrated value of the battery 11 obtained by integrating all charge and discharge amounts (past values) to date. After the external charging / exchange detection unit 22 updates the current integrated value of the battery 11, the process proceeds to S203.

[0045] The current integrated value of the battery 11 derived in S202 is as follows: Figure 3 As shown in the figure below, when the absolute value of the negative value is small, it means that the battery 11 is close to being fully charged, and when the absolute value of the negative value is large, it means that the battery 11 is (relatively) far from being fully charged. Figure 3 Schematic diagram showing the current integrated value of the battery 11. The current integrated value should be close to full charge as shown by the dotted line after the battery 11 is replaced, but if the sensor or the like fails to recognize the replacement, the current integrated value will decrease as shown by the solid line. In this embodiment, such erroneous recognition is eliminated.

[0046] S203

[0047] The external charging / replacement detection unit 22 determines whether the period during which the vehicle 10 is started (the time from the start to the end of the start) exceeds the predetermined time TD (the fourth threshold value) based on the data received in the above S201. This judgment is made to determine whether the charging is fully completed. Therefore, for the predetermined time TD, the time required to determine that the battery 11 has become fully charged is set. When the external charging / replacement detection unit 22 determines that the period during which the vehicle is started exceeds the time TD (S203: Yes), the processing enters S204. On the other hand, when the external charging / replacement detection unit 22 determines that the period during which the vehicle is started is less than the time TD (S203: No), the processing enters S207.

[0048] S204

[0049] The external charging / exchange detection unit 22 derives the average current value of the battery 11. Specifically, the external charging / exchange detection unit 22 derives the average current value of the battery 11 charged and discharged during the most recent startup period of the vehicle 10, that is, during the period from the start to the end of the startup this time, based on the data received in the above S201. Since the battery 11 is charged at the rated voltage when mounted on the vehicle 10, when the average current value is close to zero, it means that the battery 11 is close to fully charged, and when the value is large, it means that the battery 11 is not fully charged. After the external charging / exchange detection unit 22 derives the average current value of the battery 11, the process proceeds to S205.

[0050] exist Figure 4 The following figure shows a schematic diagram of the average current value of the battery 11 derived in S204. Figure 4 As shown in FIG. 1 , the average current value of the battery 11 is the average current value during the vehicle startup period including the startup. If the above-mentioned time TD is short, the influence of the charging current of the battery 11 after startup becomes large, resulting in an increase in the average current value. Therefore, it is preferable to set the time TD to a time that can sufficiently ignore the influence of the current fluctuation after startup.

[0051] S205

[0052] The external charging / exchange detection unit 22 determines whether the current integrated value of the battery 11 is less than a predetermined integrated value Ahe (less than a first threshold value), and whether the current average value of the battery 11 is greater than zero and less than a predetermined current value Ice (less than a second threshold value). This determination is performed to determine whether there is no contradiction between the current integrated value and the current average value with respect to the state of charge of the battery 11. For the integrated value Ahe, an arbitrary value (for example, "-10Ah") greater than the current integrated value that can be obtained when the battery 11 is in a state close to full charge is set. In addition, for the current value Ice, an arbitrary value (for example, "2.5A") greater than the current that can be obtained when the battery 11 is in a state close to full charge is set. The integrated value Ahe and the current value Ice can be appropriately set based on the capacity and performance of the battery 11, the specifications required by the vehicle 10, and the like. When the external charging / exchange detection unit 22 determines that the current integrated value of the battery 11 is less than the integrated value Ahe, and the current average value of the battery 11 is greater than zero and less than the current value Ice (S205: Yes), the process proceeds to S206. On the other hand, when the external charging / exchange detection unit 22 determines that the current integrated value of the battery 11 is greater than the integrated value Ahe or the current average value of the battery 11 is less than zero or greater than the current value Ice (S205: No), the process proceeds to S207.

[0053] S206

[0054] The external charging / exchange detection unit 22 increases the number of determination times X by 1, and the number of determination times X is used to count the number of times the determination of the above S205 is set to "true". In addition, the number of determination times X is based on the determination that there is external charging or replacement of the battery 11, and is cleared to zero by resetting parameters used in other logics for determining the exhaustion of the battery 11, for example. After the number of determination times X is increased by 1 by the external charging / exchange detection unit 22, the process proceeds to S207.

[0055] S207

[0056] The external charging / exchange detection unit 22 determines whether the determination number X exceeds the predetermined number ct1 (third threshold value). This determination is performed to avoid false detection due to the influence of noise, etc., and the predetermined number ct1 is set to an arbitrary value (for example, "5 times") that can improve the determination accuracy. In the case where the external charging / exchange detection unit 22 determines that the determination number X exceeds the number ct1 (S207: Yes), the process proceeds to S208. On the other hand, in the case where the external charging / exchange detection unit 22 determines that the determination number X is less than the number ct1 (S207: No), the process proceeds to S209.

[0057] S208

[0058] The external charging / exchange detection unit 22 sets a detection flag indicating that external charging or replacement of the battery 11 is detected to "ON" (True). In response to the detection flag being set to "ON", the data output unit 23 can perform the required processing. After the external charging / exchange detection unit 22 sets the detection flag to "ON", the battery replacement and other determination control ends.

[0059] S209

[0060] The external charging / exchange detection unit 22 sets the detection flag to "OFF" (False) indicating detection of external charging or replacement of the battery 11. After the external charging / exchange detection unit 22 sets the detection flag to "OFF", the battery replacement etc. determination control ends.

[0061] The battery replacement and other determination control of the first embodiment described above utilizes the phenomenon that the charging current decreases when the battery 11 is in a fully charged state (SOC=100%) while the vehicle 10 is running. In the battery replacement and other determination control of the first embodiment, if the number of times that the current cumulative value during running is less than the first threshold and the average current value is less than the second threshold exceeds the third threshold, it is determined that the battery 11 has been externally charged or replaced. This method makes it easy to detect external charging or replacement of the battery 11 without using a voltage that varies due to interference.

[0062] (2) Second Embodiment

[0063] Figure 5A and Figure 5B This is a flowchart for explaining the processing procedure of the second embodiment of the battery replacement determination control executed by the battery management device 20. The second embodiment is a method that focuses on the SOC dependency of the voltage of the battery 11 and utilizes the direction of the starting voltage change and the direction of the current integrated value change. Figure 5A Processing and Figure 5B The processing is connected by the combiners M and N respectively. Figure 5A and Figure 5B The battery replacement and other determination control illustrated is repeatedly started, for example, every time the ignition of the vehicle 10 is turned on (IG-ON) and the vehicle 10 is started.

[0064] S501

[0065] The data receiving unit 21 receives data transmitted from the data transmitting unit 13 of the vehicle 10. The data received by the data receiving unit 21 includes at least information about the current and voltage of the battery 11. The received data may be stored in a predetermined storage unit (not shown) or the like. After the data receiving unit 21 receives the data, the process proceeds to S502.

[0066] S502

[0067] The external charging / replacement detection unit 22 determines whether the parking time of the vehicle 10 before receiving the data in the above S501 is longer than the predetermined time (the 7th threshold value). That is, the external charging / replacement detection unit 22 determines whether the time from the last start of the vehicle 10 to the current start has passed longer than the predetermined time. This judgment is performed to determine whether the starting voltage of the battery 11 is affected by polarization. When the external charging / replacement detection unit 22 determines that the parking time of the vehicle 10 is longer than the predetermined time (S502: Yes), the processing enters S503. On the other hand, when the external charging / replacement detection unit 22 determines that the parking time of the vehicle 10 is less than the predetermined time (S502: No), the processing enters S508.

[0068] S503

[0069] The external charging / exchange detection unit 22 updates (derives) the current integrated value of the battery 11. Specifically, the external charging / exchange detection unit 22 calculates the charge and discharge amount (this value) of the battery 11 from the last start to the current start based on the current (this value) of the battery 11 included in the data received in S501. Then, the calculated charge and discharge amount (this value) is added to the current integrated value of the battery 11 obtained by integrating all charge and discharge amounts (past values) up to now. After the external charging / exchange detection unit 22 updates the current integrated value of the battery 11, the process proceeds to S504.

[0070] S504

[0071] The external charging / exchange detection unit 22 derives the difference value of the starting voltage of the battery 11. Specifically, based on the data received in the above S501, the external charging / exchange detection unit 22 derives the difference value between the starting voltage of the battery 11 at this startup (this value) and the starting voltage of the battery 11 at the last startup (last value), that is, the first voltage difference (=this value-last value). After the external charging / exchange detection unit 22 derives the difference value of the starting voltage, the process proceeds to S505.

[0072] exist Figure 6 The above figure shows a schematic diagram of the difference value of the starting voltage of the battery 11 derived in S504. Figure 6 As shown in FIG. 1 , the difference value (first voltage difference) of the starting voltage of the battery 11 is the voltage difference between the starting voltages of the battery 11 before and after each measured voltage.

[0073] Here, the starting voltage of the battery 11 used to derive the first voltage difference preferably uses a corrected value after eliminating the deviation (fluctuation) factors (main causes) caused by temperature, current, and polarization from the actual measured value. As shown in the following formula 1, by adding a value obtained by multiplying a coefficient A based on the starting voltage at 25 degrees as a reference temperature by the difference between 25 degrees and the actual measured temperature to the actual measured value of the starting voltage of the battery 11, the deviation factor caused by temperature can be eliminated. In addition, as shown in the following formula 2, by adding a value obtained by multiplying a coefficient B based on the starting voltage at 40 amperes as a reference starting current by the difference between 40 amperes and the actual measured current to the starting voltage of the battery 11 after temperature correction, the deviation factor caused by current can be further eliminated. In addition, the deviation factor caused by polarization can be eliminated by using the starting voltage after the vehicle 10 has been parked for a predetermined time or longer (the above-mentioned S502 process).

[0074] Temperature-corrected starting voltage = measured starting voltage + coefficient A × (25°C - measured temperature) ... [Formula 1]

[0075] Current temperature corrected starting voltage = temperature corrected starting voltage + coefficient B × (40A - measured current) ... [Formula 2]

[0076] S505

[0077] The external charging / replacement detection unit 22 derives a voltage conversion value of the difference in the current integrated value of the battery 11. Specifically, the external charging / replacement detection unit 22 calculates the difference (= this value - last value) between the integrated value of the current charged and discharged by the battery 11 up to the current start (this value) and the integrated value of the current charged and discharged by the battery 11 up to the last start (last value) based on the current integrated value updated in the above S503. Then, a second voltage difference is derived as a value obtained by converting the calculated difference into a voltage. This conversion is performed by dividing the difference in the current integrated value by a predetermined coefficient (e.g., "10") for converting the change in the current integrated value into a change in the voltage. After the voltage conversion value of the difference in the current integrated value is derived by the external charging / replacement detection unit 22, the process enters S506.

[0078] exist Figure 6 The following figure shows a schematic diagram of the difference value of the current integrated value of the battery 11 derived in S505. Figure 6 As shown in FIG. 5 , the difference value of the current integrated value of the battery 11 (before voltage conversion) is the difference between the current integrated values ​​before and after the current integrated value of the battery 11. The difference of the current integrated value is converted into a voltage value using a coefficient. In addition, the difference value of the current integrated value of the battery 11 before the voltage conversion becomes the same value as the charge and discharge amount of the battery 11 from the last start to the current start (this value) used to update the current integrated value of the battery 11 in the above S503.

[0079] S506

[0080] The external charging / exchange detection unit 22 determines whether the value obtained by subtracting the second voltage difference, which is the voltage conversion value of the difference in the current integrated value, from the first voltage difference, which is the difference value of the starting voltage of the battery 11, is greater than a predetermined voltage value dVce (fifth threshold). This determination is performed to determine whether there is no contradiction between the first voltage difference and the second voltage difference, which have the same change direction. For the voltage value dVce, a value greater than zero (for example, "2") is set to avoid erroneous determination of the voltage deviation. When the external charging / exchange detection unit 22 determines that the value obtained by subtracting the second voltage difference from the first voltage difference is greater than the voltage value dVce (S506: Yes), the processing enters S507. On the other hand, when the external charging / exchange detection unit 22 determines that the value obtained by subtracting the second voltage difference from the first voltage difference is less than the voltage value dVce (S506: No), the processing enters S508.

[0081] S507

[0082] The external charging / exchange detection unit 22 increases the number of determinations Y by 1, and the number of determinations Y is used to count the number of times the determination in S506 is set to "true". In addition, the number of determinations Y is based on the determination that there is external charging or replacement of the battery 11, and is cleared to zero by resetting parameters used in other logics for determining the exhaustion of the battery 11, for example. After the number of determinations Y is increased by 1 by the external charging / exchange detection unit 22, the process proceeds to S508.

[0083] S508

[0084] The external charging / replacement detection unit 22 determines whether the determination number Y exceeds the predetermined number ct2 (the sixth threshold value). This determination is performed to avoid false detection caused by the influence of noise, etc., and the predetermined number ct2 is set to an arbitrary value that can improve the determination accuracy (for example, "5 times"). In addition, the number ct2 can be the same value as the number ct1 described in the above-mentioned first embodiment, or a different value therefrom. When the external charging / replacement detection unit 22 determines that the determination number Y exceeds the number ct2 (S508: Yes), the processing enters S509. On the other hand, when the external charging / replacement detection unit 22 determines that the determination number Y is less than the number ct2 (S508: No), the processing enters S510.

[0085] S509

[0086] The external charging / exchange detection unit 22 sets a detection flag indicating that external charging and / or replacement of the battery 11 is detected to "ON". In response to the detection flag being set to "ON", the data output unit 23 can perform required processing. After the external charging / exchange detection unit 22 sets the detection flag to "ON", the battery replacement and other determination control ends.

[0087] S510

[0088] The external charging / exchange detection unit 22 sets the detection flag indicating that external charging or replacement of the battery 11 has been detected to "OFF". After the external charging / exchange detection unit 22 sets the detection flag to "OFF", the battery replacement etc. determination control ends.

[0089] The battery replacement determination control of the second embodiment described above focuses on the direction of change of the starting voltage of the battery 11 and the direction of change of the current integrated value. In the battery replacement determination control of the second embodiment, if the deviation (difference) between the difference value (first voltage difference) of the starting voltage of the battery 11 and the voltage conversion value (second voltage difference) of the difference of the current integrated value is greater than the fifth threshold value, it is determined that the battery 11 has been externally charged or replaced. This method can easily detect external charging or replacement of the battery 11 while suppressing the influence of interference on the voltage and eliminating the influence of the cumulative error on the current integrated value.

[0090] (3) Third Embodiment

[0091] Figure 7 1 is a flowchart for explaining the processing procedure of the third embodiment of the battery replacement and other determination control executed by the battery management device 20. The third embodiment is a method using the moving average value of the starting voltage. Figure 7 The battery replacement and other determination control illustrated is repeatedly started, for example, every time the ignition of the vehicle 10 is turned on (IG-ON) and the vehicle 10 is started.

[0092] S701

[0093] The data receiving unit 21 receives data transmitted from the data transmitting unit 13 of the vehicle 10. The data received by the data receiving unit 21 includes at least information about the current and voltage of the battery 11. The received data may be stored in a predetermined storage unit (not shown) or the like. After the data receiving unit 21 receives the data, the process proceeds to S702.

[0094] S702

[0095] The external charging / exchange detection unit 22 updates (derives) the current integrated value of the battery 11. Specifically, the external charging / exchange detection unit 22 calculates the charge and discharge amount (this value) of the battery 11 from the last start to the current start based on the current (this value) of the battery 11 included in the data received in S701. Then, the calculated charge and discharge amount (this value) is added to the current integrated value of the battery 11 obtained by integrating all charge and discharge amounts (past values) to date. After the external charging / exchange detection unit 22 updates the current integrated value of the battery 11, the process proceeds to S703.

[0096] S703

[0097] The external charging / replacement detection unit 22 derives a moving average coefficient α1 for updating the voltage reference value. The voltage reference value (VEMA1) is a voltage value that is sequentially updated using the moving average coefficient α1 calculated in this S703 with the predetermined voltage of the battery 11 as the initial voltage. Examples of the initial voltage include the voltage of the battery 11 when it is new, the voltage when it is fully charged by an external charger, and the like. The moving average coefficient α1 is a coefficient that changes according to the difference between the starting voltage of the battery 11 at this start and the voltage reference value updated at the last start, and can be set, for example, as follows: Figure 8 As shown in the figure, the moving average coefficient α1 decreases exponentially with the increase of the difference value. Figure 8 The moving average coefficient α1 may be extracted from such a data map or calculated by a predetermined calculation formula. After the external charging / exchange detection unit 22 derives the moving average coefficient α1, the process proceeds to S704.

[0098] S704

[0099] The external charging / exchange detection unit 22 updates (derives) the voltage reference value. Specifically, the external charging / exchange detection unit 22 uses the moving average coefficient α1 derived in S703 to update the voltage reference value according to the relative difference from the starting voltage of the battery 11 according to the following formula 3. As can be seen from the formula 3, the larger the difference between the voltage reference value and the starting voltage, the smaller the moving average coefficient α1 ( Figure 8 ), so the voltage change amount of the voltage reference value is smaller. Therefore, when the deviation between the voltage reference value and the starting voltage is large, even if it is updated, the updated voltage reference value is almost unchanged from the previous voltage reference value, and is substantially maintained at the voltage before the update. After the voltage reference value is updated by the external charging / exchange detection unit 22, the process enters S705.

[0100] Updated voltage reference value = (1-α1) × voltage reference value + α1 × starting voltage ... [Equation 3]

[0101] S705

[0102] The external charging / replacement detection unit 22 derives a moving average coefficient α2 for updating the voltage reference value. The voltage reference value (VEMA2) is a voltage value that is sequentially updated using the moving average coefficient α2 calculated in this S705, with the predetermined voltage of the battery 11 as the initial voltage. The initial voltage uses the same value as the initial voltage of the voltage reference value. The moving average coefficient α2 is a coefficient that changes according to the difference between the starting voltage of the battery 11 at the current start and the starting voltage of the battery 11 at the last start (= this value - last value). The moving average coefficient α2 can be set, for example, as follows: Fig. 9As shown in FIG. 1 , the moving average coefficient α2 is a value that decreases exponentially with the increase in the difference value. The moving average coefficient α2 is basically set to a value larger than the moving average coefficient α1 described above. The moving average coefficient α2 can be obtained from Fig. 9 After the moving average coefficient α2 is derived by the external charging / exchange detection unit 22, the process proceeds to S706.

[0103] S706

[0104] The external charging / exchange detection unit 22 updates (derives) the voltage reference value. Specifically, the external charging / exchange detection unit 22 uses the moving average coefficient α2 derived in the above S705 to update the voltage reference value according to the following formula 4. As can be seen from the formula 4, the greater the difference between the previous starting voltage and the current starting voltage, the smaller the moving average coefficient α2 ( Fig. 9 ), so the voltage change amount of the voltage reference value is smaller. Therefore, in the case where the starting voltage has a large change between the last time and this time, even if it is updated, the updated voltage reference value is almost unchanged from the last voltage reference value, and the influence of noise is eliminated. After the voltage reference value is updated by the external charging / exchange detection unit 22, the process enters S707.

[0105] Updated voltage reference value = (1-α2) × voltage reference value + α2 × starting voltage ... [Formula 4]

[0106] As described in the second embodiment, the starting voltage of the battery 11 used in S703 to S706 is preferably a corrected value obtained by excluding the variation factors due to temperature, current and polarization from the actual measured value.

[0107] S707

[0108] The external charging / replacement detection unit 22 determines whether the value obtained by subtracting the voltage reference value from the voltage reference value is greater than a predetermined voltage value (the eighth threshold value). This determination is performed to determine whether there is no contradiction between the voltage reference value and the voltage reference value that undergo the same change. The predetermined voltage value can be appropriately set according to the performance of the battery 11, the required detection performance, etc. In addition, in this S707, it is also possible to simply determine whether the voltage reference value is greater than the voltage reference value without using the predetermined voltage value. In the case where the external charging / replacement detection unit 22 determines that the value obtained by subtracting the voltage reference value from the voltage reference value is greater than the predetermined voltage value (S707: Yes), the processing enters S708. On the other hand, in the case where the external charging / replacement detection unit 22 determines that the value obtained by subtracting the voltage reference value from the voltage reference value is less than the predetermined voltage value (S707: No), the processing enters S709.

[0109] S708

[0110] The external charging / exchange detection unit 22 sets a detection flag indicating that external charging or replacement of the battery 11 is detected to "ON". In response to the detection flag being set to "ON", the data output unit 23 can perform required processing. After the external charging / exchange detection unit 22 sets the detection flag to "ON", the battery replacement and other determination control ends.

[0111] S709

[0112] The external charging / exchange detection unit 22 sets the detection flag indicating that external charging or replacement of the battery 11 has been detected to "OFF". After the external charging / exchange detection unit 22 sets the detection flag to "OFF", the battery replacement etc. determination control ends.

[0113] The battery replacement and other determination control of the third embodiment described above uses the moving average value of the voltage of the battery 11, and when the value obtained by subtracting the voltage reference value from the voltage reference value is greater than a predetermined voltage value, it is determined that the battery 11 has been externally charged or replaced. This method makes it possible to easily detect external charging or replacement of the battery 11 by adjusting the moving average value of the voltage with a logic that uses only the voltage value while removing the influence of interference on the voltage.

[0114] Application Examples

[0115] The first embodiment, the second embodiment, and the third embodiment of the battery replacement and other determination control described above can be appropriately combined and executed. Fig. 10A , Fig. 10B and Fig. 10C Detailed Description of the Invention A flowchart showing the processing steps of the battery replacement and other determination control combining the first embodiment and the second embodiment is shown. Fig. 10A , Fig. 10B and Fig. 10C Each processing is connected by the combiners R and S.

[0116] In each process of the battery replacement and other determination control of this application example, Figure 2 , Figure 5A and Figure 5B The processing of the same step number performs the same processing as that of the first embodiment and the second embodiment. Hereinafter, the determination control of battery replacement etc. corresponding to the use case will be described, centering on the processing different from the first embodiment and the second embodiment.

[0117] exist Fig. 10AIn the case where the external charging / replacement detection unit 22 determines that the vehicle startup period is less than the time TD (S203: No), in the case where it is determined in S205 that the current cumulative value of the battery 11 is greater than the cumulative value Ahe or the current average value of the battery 11 is less than zero or greater than the current value Ice (S205: No), and the number of determinations X is increased by 1 (S206), the processing enters S502.

[0118] exist Fig. 10B In the case where the external charging / replacement detection unit 22 determines that the parking time of the vehicle 10 is less than the predetermined time (S502: No), determines that the value obtained by subtracting the second voltage difference from the first voltage difference is less than the voltage value dVce (S506: No), and increases the number of determinations Y by 1 (S507), the processing enters S1001.

[0119] exist Fig. 10C In S1001, the external charging / exchange detection unit 22 determines whether the determination number X exceeds the predetermined number of times ct1 (third threshold) and whether the determination number Y exceeds the predetermined number of times ct2 (sixth threshold). In addition, when the external charging / exchange detection unit 22 determines that the determination number X exceeds the number of times ct1 or determines that the determination number Y exceeds the number of times ct2 (S1001: Yes), the process proceeds to S208. On the other hand, when the external charging / exchange detection unit 22 determines that the determination number X does not exceed the number of times ct1 and the determination number Y does not exceed the number of times ct2 (S1001: No), the process proceeds to S209.

[0120] Thus, in the battery replacement and other determination control of the application example, if the final result (S1001) of either the determination based on the first embodiment or the determination based on the second embodiment is "true", it is determined that the battery 11 has been externally charged or replaced. As a result, the accuracy of detecting whether the battery has been externally charged or replaced is improved compared to the case where a single embodiment is implemented.

[0121] Function / Effect

[0122] As described above, according to an embodiment of the present disclosure, the battery management device 20 involves, using information such as the cumulative value, average value, and starting voltage of the battery 11 that can be easily obtained, to determine the inconsistency of the battery state (difference in change direction, deviation in value, etc.) caused by the fact that the logical parameters required to manage the battery 11 were not reset when the battery 11 was externally charged or replaced.

[0123] This control makes it possible to accurately detect that the battery 11 is externally charged or that the battery 11 is replaced, without using a complicated equivalent circuit model that increases the processing load.

[0124] The battery management device of the present disclosure can be used to determine whether a battery mounted on a vehicle has been externally charged or replaced.

Claims

1. A battery management device is a device for managing a battery mounted on a vehicle, comprising: an acquisition unit that acquires data including information on the current of the battery and information on the start of the vehicle from the vehicle; a deriving unit that derives, based on the data, a cumulative value of the battery charge and discharge currents up to now and an average value of the battery charge and discharge currents during a recent start-up period of the vehicle; and The determination unit determines that the battery has been externally charged or replaced when the integrated value of the current is smaller than a first threshold value and the average value of the current is smaller than a second threshold value.

2. The battery management device according to claim 1, The deriving unit derives the integrated value of the current and the average value of the current every time the vehicle is started, The determination unit determines that the battery has been externally charged or replaced when the number of times that the integrated value of the current is less than the first threshold and the average value of the current is less than the second threshold exceeds a third threshold.

3. The battery management device according to claim 1 or 2, The determination unit does not perform determination when the startup period of the vehicle is less than a fourth threshold value.

4. A battery management device is a device for managing a battery mounted on a vehicle, comprising: an acquisition unit that acquires data including information on the current and voltage of the battery from the vehicle when the vehicle is started; a deriving unit that derives a first voltage difference and a second voltage difference based on the data, the first voltage difference being a difference between a starting voltage of the battery at this start and a starting voltage of the battery at a previous start, and the second voltage difference being a difference between a cumulative value of a charge and discharge current of the battery until this start and a cumulative value of a charge and discharge current of the battery until a previous start, converted into a voltage; and The determination unit determines that the battery has been externally charged or replaced when a value obtained by subtracting the second voltage difference from the first voltage difference exceeds a fifth threshold value.

5. The battery management device according to claim 4, The deriving unit derives the first voltage difference by converting the starting voltage of the current state of the battery acquired by the acquiring unit into a starting voltage at a predetermined reference temperature and reference starting current of the battery.

6. The battery management device according to claim 4 or 5, The determination unit determines that the battery has been externally charged or replaced when the number of times a value obtained by subtracting the second voltage difference from the first voltage difference exceeds the fifth threshold value exceeds a sixth threshold value.

7. The battery management device according to claim 4 or 5, The determination unit does not make a determination when the time from when the vehicle was started the last time to when it is started this time is less than a seventh threshold value.

8. A battery management device is a device for managing a battery mounted on a vehicle, comprising: an acquisition unit that acquires data including information on the current and voltage of the battery from the vehicle when the vehicle is started; a deriving unit configured to derive a voltage reference value and a voltage reference value based on the data, the voltage reference value being a value obtained by updating a predetermined initial voltage according to a relative difference from a starting voltage of the battery at startup, and the voltage reference value being a value obtained by updating the initial voltage according to a difference between the starting voltage of the battery at this startup and the starting voltage of the battery at a previous startup; and The determination unit determines that the battery has been externally charged or replaced, when a value obtained by subtracting the voltage reference value from the voltage reference value exceeds an eighth threshold value.

9. The battery management device according to claim 8, The derivation unit derives the voltage reference value such that the voltage change from the last time to the present time is smaller when the difference between the starting voltage of the battery at the present start and the voltage reference value updated at the last start is larger, and derives the voltage reference value such that the voltage change from the last time to the present time is smaller when the difference between the starting voltage of the battery at the present start and the starting voltage of the battery at the last start is larger.

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